# Programme Algebra Retrieval Benchmark

**Generated:** 26 October 2026

**Replacement verdict:** **OPEN — benchmark not qualified**

## Outcome

The algebraic projection materially widens retrieval: on the original holdout it raises Recall@10 from **0.333** to **1.000** and MRR from **0.222** to **0.337**, principally by recovering JSON ledgers, transformation sources and empirical-return records absent from Markdown search. It is not a drop-in replacement: algebra-only ranking worsens the prose lineage cases, naive score fusion fails, and the keyword intent router does not pass its separately frozen validation stratum.

The later, separately frozen typed-facet candidate scores Recall@10 **1.000** and MRR **0.492**. This is evidence about an explicit source-kind interface, not permission to erase the failed router result or replace canonical retrieval.

## Metrics

Each cell is Recall@10 / mean reciprocal rank.

| Split | Cases | Canonical | Algebra | Naive fusion | Routed |
|---|---:|---:|---:|---:|---:|
| calibration | 6 | 0.333 / 0.250 | 1.000 / 0.487 | 0.833 / 0.380 | 0.833 / 0.546 |
| holdout | 6 | 0.333 / 0.222 | 1.000 / 0.337 | 0.667 / 0.432 | 1.000 / 0.480 |
| validation | 6 | 0.167 / 0.083 | 0.500 / 0.124 | 0.500 / 0.141 | 0.500 / 0.124 |
| faceted-validation | 6 | 0.333 / 0.333 | 1.000 / 0.242 | 1.000 / 0.492 | 1.000 / 0.492 |

## Case ledger

| Split | Case | Canonical rank | Algebra rank | Fusion rank | Routed rank |
|---|---|---:|---:|---:|---:|
| calibration | calibration-hydrodynamic-lineage | 1 | 7 | 1 | 1 |
| calibration | calibration-e8-edge-lineage | 2 | 9 | 3 | 9 |
| calibration | calibration-complete-experiment-programmes | — | 1 | 2 | 1 |
| calibration | calibration-incomplete-experiment-atlas | — | 2 | — | — |
| calibration | calibration-instrumentation-return | — | 6 | 9 | 6 |
| calibration | calibration-defeat-graph | — | 1 | 3 | 1 |
| holdout | holdout-detector-route-refusal | 3 | 7 | 1 | 3 |
| holdout | holdout-casimir-platform-route | 1 | 3 | 1 | 1 |
| holdout | holdout-th229-incomplete-return | — | 3 | 9 | 3 |
| holdout | holdout-evidence-spine-records | — | 1 | 3 | 1 |
| holdout | holdout-claimipedia-publication-batch | — | 10 | 13 | 10 |
| holdout | holdout-d02-boundary-source | — | 9 | 14 | 9 |
| validation | validation-complexity-cards | — | — | — | — |
| validation | validation-detector-register | — | 17 | — | 17 |
| validation | validation-mystery-distance | — | 5 | 6 | 5 |
| validation | validation-open-topics | — | 5 | 9 | 5 |
| validation | validation-e8-tomography-prose | 2 | 5 | 2 | 5 |
| validation | validation-wave-gate-audit | — | 12 | 15 | 12 |
| faceted-validation | faceted-continuation-map | — | 6 | 6 | 6 |
| faceted-validation | faceted-admissibility-zone-register | — | 3 | 3 | 3 |
| faceted-validation | faceted-quarter-turn-propagation-audit | — | 4 | 4 | 4 |
| faceted-validation | faceted-documentation-gate | — | 5 | 5 | 5 |
| faceted-validation | faceted-transverse-detector-prose | 1 | 3 | 1 | 1 |
| faceted-validation | faceted-fixed-index-defect-prose | 1 | 6 | 1 | 1 |

## Failed replacement gates

- `routedValidationMarkdownNonRegressing`
- `routedValidationMachineRecoveredAt10`

## Implications

1. **Keep both indices.** Canonical Markdown search remains better for ordinary prose and exact conceptual destinations.
2. **Use algebra for source classes the current index cannot see.** JSON records, empirical packets, explicit refusals and transformation-family sources are the demonstrated gain.
3. **Do not average scores blindly.** The retained fusion control buries machine sources without reliably improving prose.
4. **Do not infer output lane from broad keywords alone.** “Protocol” can name a prose research document as easily as a machine schema.
5. **Treat source kind as an explicit selector.** The typed facet is a user- or query-planner declaration, not a semantic fact inferred from loose vocabulary.
6. **Next gate:** test typed facets on a larger untouched query set, then compare reasoning answers and provenance—not retrieval alone—before considering replacement.

## Authority boundary

Expected sources test navigation and structural recovery only. They do not establish the truth, completeness or scientific authority of any source.

- Corpus digest: `d09c3db276dab1800bf0c8555418fdd25151f4ab9214af40e9bb4aafb80c940c`
- Algebra archive: `df63624275ec89aa7548340c5743f69ac28e9b9304b14ee52f7b086169dfaa7c`
- Suite: `2fc979749f8788ff56b3278fa4c510af05127ae56c34fdac57393268a834cb64`